Mercer County is in Great Lakes & Wilds Pennsylvania. Of the 67 counties in the Keystone State, 682-square-mile Mercer County ranks 33rd by size. There is about 1,000 acres of farms for sale in Pennsylvania's Mercer County based on recent Land Network data. The combined market value of farms and rural land for sale here is nearly $4 million. The average price of farms for sale in Mercer County was $330,269. Farms for sale in Mercer County support livestock including horses, cattle, sheep, pig and goats. Browse all Pennsylvania farms for sale on the Land Network to find the farm, cattle operation, hobby farm or other farm property that's right for your future business or lifestyle needs.